May 27, 2026 • 10 mins
Does knuckle cracking give you arthritis? It doesn't appear to. But that doesn't mean it's harmless.
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Speaker 1 (00:04):
Hey, and welcome to the Short Stuff, Josh, Chuck. Cheerry's
sitting in for day, So this is short stuff. Chuck.
I have a question for you. Are you cracking your
knuckles right now?
Speaker 2 (00:16):
I am. Did you hear that?
Speaker 1 (00:17):
Yeah, that wasn't like a like a foldy effect.
Speaker 2 (00:21):
No, I was cracking my knuckles. I'm a knuckle cracker.
I don't do it. I did it a lot when
I was a kid, but I still do it some.
Speaker 1 (00:30):
This is what my knuckles sound like when I crack them.
That's it the Yeah, I can't do it again because
I have to wait twenty to thirty minutes for the
airbus to come back and cavitate once more.
Speaker 2 (00:49):
Yeah, we'll tell everybody what's going on here. What I know.
There was a lot of you know, when you're young,
everyone was like, it'll give you arthritis, and it's your
your bones grinding together, and that's what racking your knuckles
as and that can't be good for you.
Speaker 1 (01:02):
Yes, if your bones ground together, you would not be
able to think of anything else but your bones grinding together,
because you would be in so much pain that you
would know your bones are grinding together. That's not what
cracking your knuckles is it turns out instead, it has
everything to do with the space and the area around
where your bones come together. Your bones don't actually come.
Speaker 2 (01:24):
Together, that's right, where there's a joint that is where
two bones meet, but they're separate and they're held together
by ligaments and connected tissues and all that stuff. But
there's also some a very other key ingredient in there.
It's called synovial fluid. It's a thick, clear liquid that
kind of encases that area, right.
Speaker 1 (01:45):
Yeah, it's thick, it tastes just like orange crush CRUs surprisingly.
And when you pop your knuckle, what you're doing is
stretching or bending the ligaments and connective tissues and the
cyanoval fluid there too. Right. So when you do that,
that capsule is what it's called the connective tissue capsule
that includes the synovial fluid. It gets stretched, which increases
(02:09):
its volume, and then suddenly the pressure inside the capsule
in that synovial fluid it goes down. It decreases in pressure,
which means that all these gases that used to just
be part of the solution now are part of the problem.
I mean now turn into bubbles.
Speaker 2 (02:26):
That's right. So they become you know, they form those bubbles,
and if you stretch that joint far enough, like you know,
trying to crack your knuckles, the pressure in the capsule
goes so low that it just pops those bubbles. And
that's the popping sound that we're hearing.
Speaker 1 (02:41):
There, you go, not your bones rubbing together? Okay, I
want you to go to recess and tell your friends
that is not your bones rubbing together.
Speaker 2 (02:50):
Yeah. And then the cavitation you mentioned earlier, I think
before we break, we should just clear that up. You
said twenty to thirty minutes. That is how long it
takes for that gas to reach dissolve into that joint fluid,
and uh, cavitation is is possible again.
Speaker 1 (03:09):
My knuckles?
Speaker 2 (03:10):
Yeah? Exactly.
Speaker 1 (03:13):
Oh I just did one again. Okay, I say we
take a little break and come back and talk about
how we know that cracking your knuckles doesn't give you arthritis.
Speaker 3 (03:22):
All right, we'll be right back, Chuck.
Speaker 1 (03:54):
I know we've talked about this guy before, doctor Donald Unger.
I think we did a video about him, but he
you know what, I'll bet we talked about him in
the Ignoble Prize episode because he won an ignoble for this,
butentually he conducted an experiment for sixty years because he
wanted to prove his mother wrong. And he only cracked
(04:15):
the knuckles and I think his left hand never cracked
him on his right hand.
Speaker 2 (04:20):
It's crazy.
Speaker 1 (04:20):
And then after sixty years he finally said, okay, it's
time and he x rayed his hands.
Speaker 2 (04:26):
Yeah, if he didn't have the compulsion to crack his knuckles,
I could see how this happened. But if you are
a knuckle cracker, you're kind of you feel compelled to
do it. So I can't imagine what it would have
taken to not crack the knuckles on one hand for
that many years. It must have been really tough. Yeah, sure,
that's my guess. So, yeah, he did this over his lifetime.
(04:49):
He x rayed himself on the rag and eventually, decades later,
came to the conclusion that he doesn't have any arthritic
difference in his hands.
Speaker 1 (05:00):
Case closed, he had nad no arthritic difference.
Speaker 2 (05:04):
That's right.
Speaker 1 (05:06):
That's not to say though, that even if you don't
get arthritis from cracking your knuckles. It's another thing you
can tell your friends at recess, did they even have
recess anymore. I guess maybe yeah, our long screen time.
Speaker 2 (05:17):
No, they have recess, Okay, great.
Speaker 1 (05:21):
There is damage that you can do from cracking your
knuckles habitually. There was a guy named Raymond Broder and
he examined three hundred people who crack their knuckles to
look at what their joints looked like, and compared to
the control group, no difference with arthritis. Again, but there
was other damage like soft tissue damage to that the
(05:42):
ligaments and the synovial fluid capsule, and that they had
a decrease in grip strength. So if you crack your
knuckles a lot, like don't even think about holding a
glass of water with just one hand.
Speaker 2 (05:56):
Yeah, which you know as you age, grip strength is important.
So it's definitely not a harmless thing. There's some other
possible side effects, something called ligament laxity, which is basically
looseness over time. If you're just doing this a lot,
that that's what leads to the reduced grip strength and
sometimes sort of overall hand function. I think in rare cases,
(06:19):
if you're if you have a really weird method or
forceful method, or you're a little too aggressive with it,
you can get some soft tissue swelling around the knuckles
in the joint.
Speaker 1 (06:30):
Yeah, and you can just straight up injure yourself. If
you you can like dislocate a joint, you can injure
your tendons. And even if you don't straight up injure yourself,
just habitually cracking your knuckles over time, the stretching of
the ligaments can it. Like you said, the grip strength
thing is a is a big deal, just even without
cracking your knuckles. So it also happens in pictures too,
(06:54):
major league pictures, imagine minor league pictures too. But over
the years, just throwing over and over and over again,
they're stretching those ligaments suddenly violently basically, which is kind
of what you're doing when you crack your knuckles. They're
just doing it with different ligaments. But that is why
Oral Hirsheiser's right arm just dangles uselessly at his side
(07:16):
because it's been ruined. He ruined it pitching.
Speaker 2 (07:19):
Yeah, I mean, I know you're kind of kidding, but
sad but true. Like, especially these days, there's been more
and more instances of Tommy John surgery being required because
pitchers are throwing harder and harder and if you're not,
you know, able to get it near one hundred miles
an hour these days, you're not gonna have much of
a chance. So it's a real problem in baseball.
Speaker 1 (07:42):
Bring down from my joke.
Speaker 2 (07:44):
Yeah, I just love that you love saying Earl Hirschheiser.
Speaker 1 (07:48):
Sure, who oughtn't say?
Speaker 2 (07:52):
Boy? He was great? There was a study in nineteen
ninety that confirmed the grip strength thing. I think they
study seventy four people who regularly crack their knuckles, and
their average grip strength was definitely lower, and they had
more instances of hand swelling than the two hundred and
twenty six people who did not crack. And another interesting
thing is they found that in another study that if
(08:14):
you're a habitual knuckle cracker, you are more likely to
be a manual laborer, more likely to bite your nails
as I do, smoke cigarettes which I don't, and drink
alcohol which I do.
Speaker 1 (08:28):
Yeah, so you know three for five.
Speaker 2 (08:32):
Yeah I don't manual labor so okay too, shouldn't count
that one.
Speaker 1 (08:36):
So there is some benefits to actually cracking your knuckles though, too.
We're not just hating on cracking your knuckles. There's something
called the Goldie tendon organs, not the Goldie apparatus. That's
a different, different episode altogether. The Goldie tenon orggans sense
muscle tension, and when you crack your knuckles, you're actually
(08:57):
relieving some muscle tension, So the muscles around the joints
when you crack them get relaxed, so you can feel like,
you know, your your hands feel pretty mellow after cracking
your knuckles. I saw it described as yoga for your knuckles.
Speaker 2 (09:13):
Oh interesting, yeah, I thought so too, So like getting
your back cracked or.
Speaker 1 (09:17):
Something basically, yeah, but for your knuckles.
Speaker 2 (09:20):
Yeah, we found one more thing, you know, Like I'm
at the age where you know, if I kneel down
to get something, you're gonna hear a couple of snap
crackle and a pop maybe. And then from some part
of my body.
Speaker 1 (09:33):
Do you make an involuntary sound too when you're getting up?
Speaker 2 (09:36):
I do, oh oh yeah, like oh god, here we.
Speaker 1 (09:38):
Go, yeah, something like that, like you can't not.
Speaker 2 (09:40):
Do it, yeah for sure. And when I walk downstairs,
my right ankle, like on every step just goes pop
pop pop. So those things happen. I don't think anyone
knows exactly where that comes. From theirs speculation. It could
be just like you know, if it's your knee, it
(10:01):
maybe your kneecap rubbing on the bones or something like that,
or maybe a tendon sliding over a bumpy surface or
something like that. So I don't think it's anything to
be alarmed about.
Speaker 1 (10:11):
It is alarming, though, for sure.
Speaker 2 (10:13):
Yeah, because it comes with age. So every new pain
and sound is like, huh, that didn't happen a few years.
Speaker 1 (10:18):
Ago, Exactly, I should go sit down for a while, right,
you got anything else for short stuff? Guy?
Speaker 2 (10:25):
I got nothing else. I can't crack my knuckles. So
oh wait, there went one recavitated.
Speaker 1 (10:31):
So what does that mean?
Speaker 3 (10:32):
Though?
Speaker 2 (10:33):
I think that means short.
Speaker 3 (10:34):
Stuff is out.
Speaker 2 (10:38):
Stuff you Should Know is a production of iHeartRadio. For
more podcasts my heart Radio, visit the iHeartRadio app, Apple Podcasts,
or wherever you listen to your favorite shows.
Hey, and welcome to the Short Stuff, Josh, Chuck. Cheerry's
sitting in for day, So this is short stuff. Chuck.
I have a question for you. Are you cracking your
knuckles right now?
Speaker 2 (00:16):
I am. Did you hear that?
Speaker 1 (00:17):
Yeah, that wasn't like a like a foldy effect.
Speaker 2 (00:21):
No, I was cracking my knuckles. I'm a knuckle cracker.
I don't do it. I did it a lot when
I was a kid, but I still do it some.
Speaker 1 (00:30):
This is what my knuckles sound like when I crack them.
That's it the Yeah, I can't do it again because
I have to wait twenty to thirty minutes for the
airbus to come back and cavitate once more.
Speaker 2 (00:49):
Yeah, we'll tell everybody what's going on here. What I know.
There was a lot of you know, when you're young,
everyone was like, it'll give you arthritis, and it's your
your bones grinding together, and that's what racking your knuckles
as and that can't be good for you.
Speaker 1 (01:02):
Yes, if your bones ground together, you would not be
able to think of anything else but your bones grinding together,
because you would be in so much pain that you
would know your bones are grinding together. That's not what
cracking your knuckles is it turns out instead, it has
everything to do with the space and the area around
where your bones come together. Your bones don't actually come.
Speaker 2 (01:24):
Together, that's right, where there's a joint that is where
two bones meet, but they're separate and they're held together
by ligaments and connected tissues and all that stuff. But
there's also some a very other key ingredient in there.
It's called synovial fluid. It's a thick, clear liquid that
kind of encases that area, right.
Speaker 1 (01:45):
Yeah, it's thick, it tastes just like orange crush CRUs surprisingly.
And when you pop your knuckle, what you're doing is
stretching or bending the ligaments and connective tissues and the
cyanoval fluid there too. Right. So when you do that,
that capsule is what it's called the connective tissue capsule
that includes the synovial fluid. It gets stretched, which increases
(02:09):
its volume, and then suddenly the pressure inside the capsule
in that synovial fluid it goes down. It decreases in pressure,
which means that all these gases that used to just
be part of the solution now are part of the problem.
I mean now turn into bubbles.
Speaker 2 (02:26):
That's right. So they become you know, they form those bubbles,
and if you stretch that joint far enough, like you know,
trying to crack your knuckles, the pressure in the capsule
goes so low that it just pops those bubbles. And
that's the popping sound that we're hearing.
Speaker 1 (02:41):
There, you go, not your bones rubbing together? Okay, I
want you to go to recess and tell your friends
that is not your bones rubbing together.
Speaker 2 (02:50):
Yeah. And then the cavitation you mentioned earlier, I think
before we break, we should just clear that up. You
said twenty to thirty minutes. That is how long it
takes for that gas to reach dissolve into that joint fluid,
and uh, cavitation is is possible again.
Speaker 1 (03:09):
My knuckles?
Speaker 2 (03:10):
Yeah? Exactly.
Speaker 1 (03:13):
Oh I just did one again. Okay, I say we
take a little break and come back and talk about
how we know that cracking your knuckles doesn't give you arthritis.
Speaker 3 (03:22):
All right, we'll be right back, Chuck.
Speaker 1 (03:54):
I know we've talked about this guy before, doctor Donald Unger.
I think we did a video about him, but he
you know what, I'll bet we talked about him in
the Ignoble Prize episode because he won an ignoble for this,
butentually he conducted an experiment for sixty years because he
wanted to prove his mother wrong. And he only cracked
(04:15):
the knuckles and I think his left hand never cracked
him on his right hand.
Speaker 2 (04:20):
It's crazy.
Speaker 1 (04:20):
And then after sixty years he finally said, okay, it's
time and he x rayed his hands.
Speaker 2 (04:26):
Yeah, if he didn't have the compulsion to crack his knuckles,
I could see how this happened. But if you are
a knuckle cracker, you're kind of you feel compelled to
do it. So I can't imagine what it would have
taken to not crack the knuckles on one hand for
that many years. It must have been really tough. Yeah, sure,
that's my guess. So, yeah, he did this over his lifetime.
(04:49):
He x rayed himself on the rag and eventually, decades later,
came to the conclusion that he doesn't have any arthritic
difference in his hands.
Speaker 1 (05:00):
Case closed, he had nad no arthritic difference.
Speaker 2 (05:04):
That's right.
Speaker 1 (05:06):
That's not to say though, that even if you don't
get arthritis from cracking your knuckles. It's another thing you
can tell your friends at recess, did they even have
recess anymore. I guess maybe yeah, our long screen time.
Speaker 2 (05:17):
No, they have recess, Okay, great.
Speaker 1 (05:21):
There is damage that you can do from cracking your
knuckles habitually. There was a guy named Raymond Broder and
he examined three hundred people who crack their knuckles to
look at what their joints looked like, and compared to
the control group, no difference with arthritis. Again, but there
was other damage like soft tissue damage to that the
(05:42):
ligaments and the synovial fluid capsule, and that they had
a decrease in grip strength. So if you crack your
knuckles a lot, like don't even think about holding a
glass of water with just one hand.
Speaker 2 (05:56):
Yeah, which you know as you age, grip strength is important.
So it's definitely not a harmless thing. There's some other
possible side effects, something called ligament laxity, which is basically
looseness over time. If you're just doing this a lot,
that that's what leads to the reduced grip strength and
sometimes sort of overall hand function. I think in rare cases,
(06:19):
if you're if you have a really weird method or
forceful method, or you're a little too aggressive with it,
you can get some soft tissue swelling around the knuckles
in the joint.
Speaker 1 (06:30):
Yeah, and you can just straight up injure yourself. If
you you can like dislocate a joint, you can injure
your tendons. And even if you don't straight up injure yourself,
just habitually cracking your knuckles over time, the stretching of
the ligaments can it. Like you said, the grip strength
thing is a is a big deal, just even without
cracking your knuckles. So it also happens in pictures too,
(06:54):
major league pictures, imagine minor league pictures too. But over
the years, just throwing over and over and over again,
they're stretching those ligaments suddenly violently basically, which is kind
of what you're doing when you crack your knuckles. They're
just doing it with different ligaments. But that is why
Oral Hirsheiser's right arm just dangles uselessly at his side
(07:16):
because it's been ruined. He ruined it pitching.
Speaker 2 (07:19):
Yeah, I mean, I know you're kind of kidding, but
sad but true. Like, especially these days, there's been more
and more instances of Tommy John surgery being required because
pitchers are throwing harder and harder and if you're not,
you know, able to get it near one hundred miles
an hour these days, you're not gonna have much of
a chance. So it's a real problem in baseball.
Speaker 1 (07:42):
Bring down from my joke.
Speaker 2 (07:44):
Yeah, I just love that you love saying Earl Hirschheiser.
Speaker 1 (07:48):
Sure, who oughtn't say?
Speaker 2 (07:52):
Boy? He was great? There was a study in nineteen
ninety that confirmed the grip strength thing. I think they
study seventy four people who regularly crack their knuckles, and
their average grip strength was definitely lower, and they had
more instances of hand swelling than the two hundred and
twenty six people who did not crack. And another interesting
thing is they found that in another study that if
(08:14):
you're a habitual knuckle cracker, you are more likely to
be a manual laborer, more likely to bite your nails
as I do, smoke cigarettes which I don't, and drink
alcohol which I do.
Speaker 1 (08:28):
Yeah, so you know three for five.
Speaker 2 (08:32):
Yeah I don't manual labor so okay too, shouldn't count
that one.
Speaker 1 (08:36):
So there is some benefits to actually cracking your knuckles though, too.
We're not just hating on cracking your knuckles. There's something
called the Goldie tendon organs, not the Goldie apparatus. That's
a different, different episode altogether. The Goldie tenon orggans sense
muscle tension, and when you crack your knuckles, you're actually
(08:57):
relieving some muscle tension, So the muscles around the joints
when you crack them get relaxed, so you can feel like,
you know, your your hands feel pretty mellow after cracking
your knuckles. I saw it described as yoga for your knuckles.
Speaker 2 (09:13):
Oh interesting, yeah, I thought so too, So like getting
your back cracked or.
Speaker 1 (09:17):
Something basically, yeah, but for your knuckles.
Speaker 2 (09:20):
Yeah, we found one more thing, you know, Like I'm
at the age where you know, if I kneel down
to get something, you're gonna hear a couple of snap
crackle and a pop maybe. And then from some part
of my body.
Speaker 1 (09:33):
Do you make an involuntary sound too when you're getting up?
Speaker 2 (09:36):
I do, oh oh yeah, like oh god, here we.
Speaker 1 (09:38):
Go, yeah, something like that, like you can't not.
Speaker 2 (09:40):
Do it, yeah for sure. And when I walk downstairs,
my right ankle, like on every step just goes pop
pop pop. So those things happen. I don't think anyone
knows exactly where that comes. From theirs speculation. It could
be just like you know, if it's your knee, it
(10:01):
maybe your kneecap rubbing on the bones or something like that,
or maybe a tendon sliding over a bumpy surface or
something like that. So I don't think it's anything to
be alarmed about.
Speaker 1 (10:11):
It is alarming, though, for sure.
Speaker 2 (10:13):
Yeah, because it comes with age. So every new pain
and sound is like, huh, that didn't happen a few years.
Speaker 1 (10:18):
Ago, Exactly, I should go sit down for a while, right,
you got anything else for short stuff? Guy?
Speaker 2 (10:25):
I got nothing else. I can't crack my knuckles. So
oh wait, there went one recavitated.
Speaker 1 (10:31):
So what does that mean?
Speaker 3 (10:32):
Though?
Speaker 2 (10:33):
I think that means short.
Speaker 3 (10:34):
Stuff is out.
Speaker 2 (10:38):
Stuff you Should Know is a production of iHeartRadio. For
more podcasts my heart Radio, visit the iHeartRadio app, Apple Podcasts,
or wherever you listen to your favorite shows.
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